I'll be going for a coilover conversion on mine without a doubt, my problem has always been what to do with the rear. I was going to talk to spax about making some upside-down coilovers (if that's even possible) that just replace the standard telescopic one, but I wasn't sure about the turrets and how strong they were or if there was enough clearance at the hub end.
If that doesn't work i think I'm left with three options...
1) new turrets built to accept S13 rear coilovers
2) The same design as Megan Racing/SE/The guys with the Z31's have done. In which case I'll look at doing something that could possibly benefit the club too.
3) Just get some new springs made for the rear and go for the Spax KSX shocks shortened so that the spring doesn't fall out when it gets the chance
I'm going drop the guys at Megan Racing an e-mail just to see if they could let me know as soon as they settled on a price and to see if they are willing to ship to the UK. I'm sure the guys on Club-S12 will post up as soon at they go on sale anyway but it won't hurt to show some further interest just in case there is a UK reseller we can go through